The invention relates generally to communication systems, and more particularly to business communication systems in which calls or other incoming communications are directed by a switch to desksets, wireless mobile telephones, or other types of user terminals within the system.
A typical business communication system includes an enterprise switch which directs calls from one or more incoming trunks to various user terminals. The user terminals may include, for example, wired desksets, wireless desksets, wireless mobile telephones and advanced terminals such as computers or video telephones. A shared communication facility within such a system is generally represented in both the switch and the corresponding terminals as a xe2x80x9cCall Appearancexe2x80x9d (CA). When a CA to a shared facility is presented on multiple user terminals, and multiple users are allowed to access this facility, the CA is known as a xe2x80x9cbridged appearance.xe2x80x9d In existing systems, such bridged appearances can generally only be defined at system administration time, for example, during an initial set-up and configuration of the system or during a subsequent system-level reconfiguration. As a result, conventional bridged appearances remain static until the system is re-administered. This conventional static architecture is generally considered best suited for wired terminals, where the operational expectation is that the user associated with a given terminal will be at his or her desk, and will be the primary or exclusive user of that terminal.
However, in systems which support wireless terminals and other more advanced equipment, users will typically have more than one terminal available to them, and may also be allowed to use the advanced equipment on a demand basis. For example, a given set of users may each have a wired deskset, a simple mobile telephone, and access on a random demand basis to an advanced shared resource such as a video telephone. Unfortunately, the above-noted conventional static bridging techniques are unable to create a dynamic bridged appearance that exists on, for example, both the mobile telephone of a given user and an advanced shared resource which happens to be located in proximity to the mobile telephone at a particular time. The conventional techniques therefore generally do not provide the user with an option of answering an incoming call directed to the mobile telephone at a co-located advanced terminal, unless the advanced terminal has been bridged with the mobile telephone during system administration. As a result, the user will often be unable to access the more sophisticated features of a nearby advanced terminal for accepting calls directed to the mobile, or placing calls as a known originator.
This invention provides a system in which users can be associated with a system terminal on a demand basis by creating a bridged call appearance that exists, for example, on both a simple mobile telephone and a co-located complex terminal such as a video telephone. This invention thus allows the creation of bridged call appearances on a dynamic demand basis. In an illustrative embodiment, a temporary association is established between a mobile terminal and at least one other system terminal. While the mobile terminal is xe2x80x9cregisteredxe2x80x9d in this manner to the other terminal, the mobile user can request permission to utilize the functions of the other terminal in order to, for example, receive incoming calls or place outgoing calls. The temporary association may be established based on a determination of the proximity of the mobile terminal to the other terminal, such that the mobile registers to different complex system terminals as it moves between different cells of the system. The temporary relationship between the mobile and a given other terminal may therefore be terminated when the mobile is no longer in proximity to that terminal. Proximity-based registration in accordance with the invention may also be implemented in an embodiment in which the proximity of a given user to a system terminal is determined by detecting a signal transmitted by a beacon device carried by the user.
The dynamic binding and bridging of the invention may be implemented using state-based processing. In an example of this type of implementation, the mobile at a given point in time may be in one of a number of states of operation, such as the following five states: (1) a null state in which there is no temporary association between the mobile and any other terminal of the system; (2) a registered state in which the temporary association is established, but the mobile user has not obtained permission to access the functions of the other terminal; (3) a bound active state in which the temporary association exists and the user is actively accessing the functions of the other terminal to conduct an on-going call; (4) a bound inactive state in which the temporary association exists and the user has obtained permission to access the functions of the other terminal, but is not currently accessing the functions; and (5) a bound alerting state in which the temporary association exists, the user has obtained permission to access the functions of the other terminal, and an in-coming call directed to the mobile generates an alerting indication on the other terminal.
Another aspect of the invention provides techniques for selecting, on a dynamic basis, an inter working function (IWF) that can modify a communication protocol to the particular format required by the bridged terminal equipment. This allows a user to bind to different terminals having different capabilities over the duration of a given call. For example, if the source terminal of the incoming call is a wireless deskset using 32 kbps voice coding and the destination terminal utilizes a DSO line at 64 kbps, the IWF may be an ADPCM-to-PCM transcoder. An IWF in accordance with the invention may also be used to insert additional data, retrieved from a database of the switch, into a reverse portion of the call directed from the destination terminal to the source terminal. For example, if the call is a video call, and the destination terminal is a terminal without video generating capability, the additional data may be video data retrieved from the database and inserted in a signal delivered from the destination terminal to the source terminal. This aspect of the invention can be used to ensure that the established bandwidth between the destination terminal and the source terminal is substantially bidirectionally symmetric.
Another aspect of the invention relates to overlaying the characteristics of a particular system terminal onto another terminal to which that user is bound. For example, when a given user enters any of the bound states noted above, permission data previously stored for that user may be overlaid onto the bound terminal so that the user may place or receive all calls in accordance with his or her normal restrictions, using the bound terminal. In an illustrative embodiment, a given system user can have multiple stored terminal profiles, one for each type of system terminal that may be accessed by that user. When the user then becomes bound to particular system terminal, the corresponding stored terminal profile of that user is overlaid onto the bound terminal. For example, if the bound terminal is of the same type as a terminal assigned to the user, the functional layout of the assigned terminal, including button assignments and soft-key label arrangements, may be overlaid on the bound terminal such that the bound terminal is configured to operate in a manner similar to the assigned terminal.